Pathway Profiling in Mycobacterium tuberculosis: ELUCIDATION OF CHOLESTEROL-DERIVED CATABOLITE AND ENZYMES THAT CATALYZE ITS METABOLISM *

摘要: Mycobacterium tuberculosis, the bacterium that causes imports and metabolizes host cholesterol during infection. This ability is important in chronic phase of Here we investigate role intracellular growth operon (igr), which has previously been identified as having a cholesterol-sensitive phenotype vitro for mycobacteria. We have employed isotopically labeled low density lipoproteins containing either [1,7,15,22,26-14C]cholesterol or [1,7,15,22,26-13C]cholesterol high resolution LC/MS tools to profile cholesterol-derived metabolome an igr operon-disrupted mutant (Δigr) M. tuberculosis. A partially metabolized species accumulated Δigr knock-out strain was absent complemented parental wild-type strains. Structural elucidation by multidimensional 1H 13C NMR spectroscopy revealed metabolite be methyl 1β-(2′-propanoate)-3aα-H-4α-(3′-propanoic acid)-7aβ-methylhexahydro-5-indanone. Heterologously expressed purified FadE28-FadE29, acyl-CoA dehydrogenase encoded operon, catalyzes dehydrogenation 2′-propanoyl-CoA ester side chains substrates with structures analogous characterized metabolite. Based on structure isolated metabolite, enzyme activity, bioinformatic annotations, assign primary function degradation 2′-propanoate chain. Therefore, necessary completely metabolize chain metabolites.